From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EFAA3C433F5 for ; Tue, 4 Oct 2022 15:23:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229534AbiJDPXo (ORCPT ); Tue, 4 Oct 2022 11:23:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230020AbiJDPXh (ORCPT ); Tue, 4 Oct 2022 11:23:37 -0400 Received: from mail-io1-f70.google.com (mail-io1-f70.google.com [209.85.166.70]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57E1E5FF49 for ; Tue, 4 Oct 2022 08:23:36 -0700 (PDT) Received: by mail-io1-f70.google.com with SMTP id 5-20020a5d9c05000000b006a44709a638so9284836ioe.11 for ; Tue, 04 Oct 2022 08:23:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date; bh=Tx70LnHgrcbySmYB773/hUxSj1SSVjuJS/a66PMZEsM=; b=5zTocD2Rip7xTIHGHk80e4jljUPBY98mwtYs+n0ZCxiVsTMiI+/1ePm4HCYQLorySF 4TcJ8gTYAjjFEZ39Q+KskeNDpf6ainjcnaK5j81OrTCeuNDVj0idE5tA3AUdXvscJLSH gHZL61t5Mo6u0klEKU4ji1ho77zqm5f8YHsJBnDSNSOx8wLLvDX8x5DhbjRLGeOpl0u8 HCmw96DHWDl/YGSW29E7RAc57KmKjNI147oskYuE2M0M+oaxu53bU0BXDuFT6tNw77lz B36OMQX0K9/TrsuLO8HrHCCJkTMje51p9vutjHt8mzIkRTFxPvznGSravKjUqk49kxc5 Pwug== X-Gm-Message-State: ACrzQf2CST7gOU8OtytZ+CcBSkr0XFD3b/qlug9g0aEguThFskJU2S94 ZnEAhxCezzOgNjgwCYd3+fkgtg6ZYk1rG1rvbLaS+MfH6cW0 X-Google-Smtp-Source: AMsMyM6j7Ur7/oUmN7yWxJ+ucCyDplXOYKtcziG2PTnNGru8ehU0o5wAwQv9X7ioK257YqLI0hI+684KFfkq5921FmTsIZJEnLiQ MIME-Version: 1.0 X-Received: by 2002:a02:5108:0:b0:35a:eca0:92c1 with SMTP id s8-20020a025108000000b0035aeca092c1mr13154892jaa.81.1664897015554; Tue, 04 Oct 2022 08:23:35 -0700 (PDT) Date: Tue, 04 Oct 2022 08:23:35 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000033295305ea370bb5@google.com> Subject: [syzbot] possible deadlock in exfat_iterate From: syzbot To: linkinjeon@kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, sj1557.seo@samsung.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: bbed346d5a96 Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=12781dbc880000 kernel config: https://syzkaller.appspot.com/x/.config?x=aae2d21e7dd80684 dashboard link: https://syzkaller.appspot.com/bug?extid=38655f1298fefc58a904 compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/11078f50b80b/disk-bbed346d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/398e5f1e6c84/vmlinux-bbed346d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+38655f1298fefc58a904@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Not tainted ------------------------------------------------------ syz-executor.5/7308 is trying to acquire lock: ffff000109945b58 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x54/0xb4 mm/memory.c:5576 but task is already holding lock: ffff00010d89e0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x74/0xcd8 fs/exfat/dir.c:228 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sbi->s_lock#2){+.+.}-{3:3}: __mutex_lock_common+0xd4/0xca8 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 exfat_get_block+0x6c/0x9ec fs/exfat/inode.c:282 do_mpage_readpage+0x474/0xd38 fs/mpage.c:208 mpage_readahead+0xf0/0x1b8 fs/mpage.c:361 exfat_readahead+0x28/0x38 fs/exfat/inode.c:345 read_pages+0x74/0x4a0 mm/readahead.c:158 page_cache_ra_unbounded+0x2cc/0x338 mm/readahead.c:263 do_page_cache_ra mm/readahead.c:293 [inline] page_cache_ra_order+0x348/0x380 mm/readahead.c:550 ondemand_readahead+0x3cc/0x724 mm/readahead.c:672 page_cache_sync_ra+0xc4/0xdc mm/readahead.c:699 page_cache_sync_readahead include/linux/pagemap.h:1215 [inline] filemap_get_pages+0x108/0x574 mm/filemap.c:2566 filemap_read+0x14c/0x6fc mm/filemap.c:2660 generic_file_read_iter+0x6c/0x25c mm/filemap.c:2806 call_read_iter include/linux/fs.h:2181 [inline] generic_file_splice_read+0xa0/0x1c8 fs/splice.c:309 do_splice_to fs/splice.c:793 [inline] splice_direct_to_actor+0x16c/0x3e4 fs/splice.c:865 do_splice_direct+0xc4/0x14c fs/splice.c:974 do_sendfile+0x298/0x68c fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1317 [inline] __se_sys_sendfile64 fs/read_write.c:1303 [inline] __arm64_sys_sendfile64+0xb0/0x230 fs/read_write.c:1303 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 -> #1 (mapping.invalidate_lock#3){.+.+}-{3:3}: down_read+0x5c/0x78 kernel/locking/rwsem.c:1499 filemap_invalidate_lock_shared include/linux/fs.h:811 [inline] filemap_fault+0x104/0x804 mm/filemap.c:3112 __do_fault+0x60/0x358 mm/memory.c:4173 do_read_fault mm/memory.c:4518 [inline] do_fault+0x338/0x550 mm/memory.c:4647 handle_pte_fault mm/memory.c:4911 [inline] __handle_mm_fault mm/memory.c:5053 [inline] handle_mm_fault+0x784/0xa40 mm/memory.c:5151 __do_page_fault arch/arm64/mm/fault.c:502 [inline] do_page_fault+0x428/0x79c arch/arm64/mm/fault.c:602 do_translation_fault+0x78/0x194 arch/arm64/mm/fault.c:685 do_mem_abort+0x54/0x130 arch/arm64/mm/fault.c:821 el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:366 el1h_64_sync_handler+0x60/0xac arch/arm64/kernel/entry-common.c:426 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:576 do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] strncpy_from_user+0x1a8/0x3d8 lib/strncpy_from_user.c:139 getname_flags+0x84/0x278 fs/namei.c:150 getname+0x28/0x38 fs/namei.c:218 do_sys_openat2+0x78/0x22c fs/open.c:1307 do_sys_open fs/open.c:1329 [inline] __do_sys_openat fs/open.c:1345 [inline] __se_sys_openat fs/open.c:1340 [inline] __arm64_sys_openat+0xb0/0xe0 fs/open.c:1340 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 -> #0 (&mm->mmap_lock){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666 __might_fault+0x7c/0xb4 mm/memory.c:5577 filldir64+0x1e4/0x56c fs/readdir.c:335 dir_emit_dot include/linux/fs.h:3547 [inline] dir_emit_dots include/linux/fs.h:3558 [inline] exfat_iterate+0xd8/0xcd8 fs/exfat/dir.c:231 iterate_dir+0x114/0x28c __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64 fs/readdir.c:354 [inline] __arm64_sys_getdents64+0x80/0x204 fs/readdir.c:354 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 other info that might help us debug this: Chain exists of: &mm->mmap_lock --> mapping.invalidate_lock#3 --> &sbi->s_lock#2 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->s_lock#2); lock(mapping.invalidate_lock#3); lock(&sbi->s_lock#2); lock(&mm->mmap_lock); *** DEADLOCK *** 3 locks held by syz-executor.5/7308: #0: ffff0000c71e8ce8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x12c/0x154 fs/file.c:1036 #1: ffff0001091738f8 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: iterate_dir+0xb8/0x28c fs/readdir.c:57 #2: ffff00010d89e0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x74/0xcd8 fs/exfat/dir.c:228 stack backtrace: CPU: 1 PID: 7308 Comm: syz-executor.5 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156 show_stack+0x2c/0x54 arch/arm64/kernel/stacktrace.c:163 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2053 check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666 __might_fault+0x7c/0xb4 mm/memory.c:5577 filldir64+0x1e4/0x56c fs/readdir.c:335 dir_emit_dot include/linux/fs.h:3547 [inline] dir_emit_dots include/linux/fs.h:3558 [inline] exfat_iterate+0xd8/0xcd8 fs/exfat/dir.c:231 iterate_dir+0x114/0x28c __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64 fs/readdir.c:354 [inline] __arm64_sys_getdents64+0x80/0x204 fs/readdir.c:354 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 --- This report is generated by a bot. 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